If you're actively trying to reduce your exposure to microplastics, there's a new study worth paying attention to because it measured something that almost never gets measured in humans. The research we usually see obsesses over how much plastic is going into your body. This study measured the opposite, how much [music] is coming out. Researchers gave a group of adults 800 mg of a supplement every day for 15 days, and by the end of it, the amount of microplastics circulating in their blood had dropped by over a quarter. I'm Dr. Yvonne Burkart, a PhD toxicologist with decades of experience studying how environmental chemicals interact with the body. In this video, I want to walk you through what these two human studies actually found, how something that stays in your gut the entire time can still change what shows up in your blood, and the honest limits of what this can and cannot reach. I hold detox claims to a high bar on this channel, and I'm going to hold this one to the exact same standard. Let's start with what's already circulating because that's the base line this study is working against. Every single participant in this research had measurable microplastic in their blood before anyone gave them anything. Not some of them, all of them. And this matters beyond the fact that it's there. According to a 2024 study in the New England Journal of Medicine, people with microplastic particles lodged in their carotid arterial plaques had a significantly higher risk of heart attack and stroke over a 3-year follow-up period. That's an association, not a confirmed cause, and I want to be clear about that distinction. But, it's the reason researchers are now asking a question that used to sound almost pointless. Can any of this actually be reduced once it's already in you? I remember reading the early studies showing microplastics in human organs, and the findings just kept coming. Then, researchers found microplastic particles in human ovarian follicular fluid, and that one hit differently for me because I spent years studying the ovary in the lab, and to think that something foreign had made it that far into that tissue felt invasive. It was one of those moments where the science stopped being abstract, and it was feeling really real. That's the research that pushed me to stop treating this as background noise and start treating it as something worth actively managing. The first study to test that question didn't even look at blood. It looked at what people were excreting. 10 volunteers took part in a crossover study, which means each person served as their own comparison. On one occasion, they ate a standardized meal with nothing added. On another, they took 0.8 g of a chitosan supplement right before the meal. Chitosan comes from the shells of crustaceans, and your body doesn't digest or absorb it. It moves straight through the gut. When researchers measured the stool samples afterward, the particle count without chitosan sat around 656. With chitosan, it jumped to 965. I want to be precise about what this first study did and didn't show. It was small, it covered a single meal, and all it demonstrated was that more plastic was leaving the body in stool. It said nothing about whether anything was actually changing on the inside. That's a different question, and it needed a different study to answer it, which is exactly what came next. In the follow-up trial, 11 adults took 800 mg of the same chitosan supplement every day for 15 days, while 10 people on placebo were tracked alongside them. Assignment wasn't fully randomized. Researchers matched people to each group by age, sex, and general lifestyle to keep the two groups comparable going in, and everyone involved was kept blind to who was getting what. Blood was drawn from each person twice, once at the very start and again after the full 15 days, always in the morning after an overnight fast, so the samples would be as comparable as possible. To identify what was in that blood, researchers used three methods together. First, a stereo microscope let them see and measure particles directly. Then, a scanning electron microscope showed the surface texture and shape of each particle, whether it was smooth, rough, angular, or worn. And infrared spectroscopy matched each particle's chemical signature against a database of more than 36,000 known compounds, which is how they were able to say not just that plastic was present, but what type of plastic it was. In the group taking chitosan, blood microplastic concentration dropped by 26.3% and that number held up with statistical testing. In the placebo group, nothing moved. So, why would something that never leaves your gut change what's floating in your bloodstream? Well, here's the mechanism. Chitosan dissolves in stomach acid and forms a gel network as it moves through the digestive tract. Microplastic particles get physically caught in that structure through ionic and hydrophobic binding. And as the gel continues through the intestine, it thickens further, holding on to what is trapped in it until it exits the body entirely. So, it never crosses into your blood. It works entirely inside the gut. But, here's what makes this counterintuitive. Blood microplastics don't just sit there permanently once they arrive. Researchers estimate that they have a residence time of about 58 days, meaning your body is constantly clearing the plastic already circulating while constantly getting a fresh supply from what you eat, drink, and breathe. So, if you can reduce how much new plastic gets absorbed through the gut, the clearance your body was already running on its own starts to outpace what's coming in and the blood level falls without a single particle being extracted from your bloodstream directly. I call this the interception effect. Nothing gets pulled out. The supply gets cut off at the gate. It's also worth knowing that the drop wasn't identical across every type of plastic. Reductions were strongest for the most common polymers found in blood, the kind that come from packaging and everyday plastic goods. Some of the more specialized plastics barely moved at all. That's actually consistent with the mechanism. Chitosan isn't selectively targeting anything. It's forming a broad physical trap, and the particles most likely to get caught are simply the ones that are showing up most often to begin with. Now, I want to be precise about who this research was done on and what it has not tested yet, because that context matters for how much weight we give these findings. Both studies were run by the same small research team, and the supplement itself is already sold commercially in Italy, which is exactly the kind of detail a viewer deserves to know before drawing conclusions. Small pilot studies from one group can still genuinely be useful as a first signal. They just haven't been independently repeated yet, and that's a meaningfully different level of evidence than something confirmed across multiple labs. The cohort in the blood study was also made up of healthcare workers living in dense urban environments, a group already dealing with a higher baseline of occupational exposure than the general population. Some of the plastic types found are associated with medical equipment, gloves, and hospital textiles rather than food and water exposure that most people deal with day-to-day. So, the specific 26% figure may not translate exactly to someone with a very different daily exposure pattern. The underlying mechanism, plastic getting trapped in the gut before it can be absorbed, isn't specific to anyone job or environment, and that part should generalize even if the exact percentage doesn't. And nanoplastics, the fraction under one micrometer that researchers increasingly think may be the most biologically active, weren't measured in this study at all, and that question is still completely open. And there's one more limit worth naming directly because it's the most important one. This interception only works on plastic that's still moving through the gut on its way into your body. It does nothing for plastic that has already settled and lodged into tissues. A 2026 study looked at whether plasma exchange, a procedure that filters blood directly, could lower circulating microplastic levels in patients. Even directly filtering the blood didn't reach what's already stored elsewhere in the body. If a method that intensive can't fully address tissue embedded plastic, that tells you something significantly about how differently deposited plastic behaves compared to what's still circulating and available for interception. And that's actually the clarifying part in a precise way. The goal was never about getting you to zero because that's impossible. Your baseline was never zero either and it never will be because exposure is constant and it comes from food, water, and the air around you. But what a study like this shows is that the body already handles most of what comes through on its own and this shifts that balance a little further in your favor. It doesn't rebuild what's already deposited and it was never designed to. At some point, I had to make peace with something that took me a while to get there and that is it's impossible to completely avoid plastic. So just looking around whatever room you're in right now, you're almost certainly touching or near plastic in some form. It's woven into modern life in a way that no individual swap fully resolves. So instead of asking how can I eliminate it all, I started asking how can I mitigate the most significant sources. That single reframe took the pressure off of perfection entirely and it's actually what made this sustainable. That's the same framework I want to leave you with today and it's the one that informs everything in the practical section that follows. So practically, where does this leave you? Reducing intake is still the highest leverage thing you can do and it's worth understanding why that remains true even with a finding like this one. Every gram of plastic that never enters your gut in the first place is one less particle competing for whatever mechanism, chitosan, or something else that might be working to intercept those particles on the way through your gut. The swaps I've covered in other videos on this channel, like water filtration, food storage, and personal care products, still do most of the work on the front end, and nothing we covered today changes that priority. There's also evidence in the fermented food space that's worth knowing about. Certain probiotic strains have been shown to bind and help excrete plastic particles, though that's mouse and bacteria data so far, not human data, and it's a different category of evidence than what we just talked about. The proposed mechanism with those studies is also different. Instead of forming a physical gel trap the way chitosan does, specific bacterial strains appear to latch directly onto plastic particles and get carried out during normal digestion. So, it's a different mechanism, but the same general direction and still early findings. If you're specifically considering chitosan, the dose studied here was 800 mg taken with meals, matching what was used in both trials. So, if you have a shellfish allergy, this is not for you, since it's derived from crustacean shells. As with any supplement, talk to your doctor before adding it in, especially if you're on other medications, since chitosan's gel-forming properties in the gut means it has a potential to interact with how other compounds get absorbed. If you want a broader framework for reducing your overall microplastic and chemical load, starting with the highest leverage swaps, the Low Tox Solution covers exactly this with a practical order of operations, so you're not guessing at what to prioritize. I'm so excited because it comes out December 1st, and it's available for pre-order now, so click the link in my description to get your copy. Everything we just walked through today lives in your bloodstream. Plastic that's actively circulating and can still be intercepted before it settles in your organs. But that raises the next obvious question. What about the plastic that's already stored? The kind sitting in fat tissue rather than moving through your blood. There's a randomized trial that tested this exact distinction using a 7-day intervention instead of a supplement. Some chemicals dropped by as much as 60% almost immediately. But one specific class, the ones that had already settled into fat, didn't move at all, not even slightly. Regardless of what people changed about their food or products that week. In the next video, I walk you through what that trial found, why some exposures respond in days while others take months or years regardless of what you do, and where your actual leverage is once you understand which kind you're dealing with. I'll see you there.